GTA 5 Lag spikes

Whenever I play GTA 5 or GTA 5 Online, the game runs perfectly. It’s really smooth, and runs well. A few minutes into the game, I get these lag spikes that last for about 3 to 8 seconds long, and it really makes the game unplayable and it’s really a struggle because I cannot aim, or shoot correctly. In a few seconds it goes away, but repeats itself. I stopped playing for a few months, but I have videos on YouTube where it never used to lag, it was perfect. I logged on recently and I was greeted with these lag spikes. I do not know what happened, I do not know if I messed up the GTA 5 settings, or if I messed up the settings for GTA 5 in my AMD Radeon settings, whatever it is, I wish it were to be fixed like it was 6 months ago, without any lag, smooth, clean, and running well. I have the settings on the near to lowest, and I know I can play higher but I just get these lag spikes that get worse the longer I play, and my PC gets louder and hotter. I think it has something to do with my graphics that I never did when I played.